Shuttleworth provided a graph, apparently from w3techs.com, indicating that Ubuntu market share among public web service users surpassed that of RHEL sometime in June 2011. Currently, according to that information, Ubuntu is leading its rival by roughly 6 million users.

"The trend is even starker if you look at what we know of new-style services, like clouds and big data, but since most of that happens behind the firewall [it's] all anecdata, while web services are a public affair," he wrote.

Shuttleworth credited improved testing and quality assurance procedures at Ubuntu maker Canonical for the upswing, as well as close collaboration between that company and the OpenStack project.

As commenters on the blog post were quick to point out, however, the statistics provided by the Ubuntu creator might not tell the whole story. One noted that the free CentOS version of RHEL is still far more popular than Ubuntu, for instance. Shuttleworth then countered by arguing that Debian - currently the top Linux distribution on web servers - should be counted as part of the Ubuntu "ecosystem," putting it back in front.

Regardless, the trends appear to be positive for Ubuntu - w3techs.com's numbers clearly show public web service numbers on the rise, from around 13 million in March 2011 to more than 18 million at present.